1. Description of the problem

Trauma to the chest and abdomen can be roughly grouped into penetrating and blunt injuries, though sometimes these injury mechanisms occur in combination.

Because infants and young children have a more pliable skeleton, the energy is transmitted to the internal viscera to a more significant degree. This can translate to a worsened injury profile in terms of internal injuries, in the absence of significant outward findings on physical exam.

Life threatening injuries to the thorax sometimes require intervention in the field or the trauma bay; conversely, life threatening injuries to the abdomen are best approached by a surgeon in the operating room.

Regardless of the location or mechanism of injury, all patients should be evaluated according to the ATLS algorithm on trauma.

Blunt Thoracic Trauma

Rib fractures: This occurs as a result of compression of the thorax, and will be accompanied by exquisite point tenderness at the site of fracture, as well as painful inspiration.

Injuries to trachea and major bronchi: initial presentation is identical to pneumothorax. May also demonstrate a mediastinal "crunch" from subcutaneous emphysema. Pneumomediastinum can be seen on chest X-ray. Pneumothorax will not resolve with placement of a chest tube.

Injuries to great vessels: often occurs near points of fixation, particularly the aorta. Physical exam findings can include hypotension, or decreased blood pressure in the lower extremities when compared to the upper extremities. A widened mediastinum will be present; other findings include pleural "capping" as blood accumulates in the apex of the pleural space.

Commotio cordis: blunt force transmitted directly to the heart which results in cessation of cardiac activity. Patients will have absent pulses on exam.

Diaphragm rupture: sudden increase in abdominal pressure from rapid deceleration transmits force up toward the diaphragm. More commonly occurs on the left than right since the liver functions to dissipate energy and protect the diaphragm. Can manifest with decreased breath sounds or fluid accumulation in the hemithorax, though diagnosis usually made with chest X-ray.

Penetrating Thoracic Trauma

Figure 1

Figure 1.

Penetrating injury to left chest

Pneumothorax: presence of air in the potential space between the parietal and visceral pleura, causing lung collapse.

The air can be entrained into the pleural space from injury to the lung parynchyma (ruptured emphysematous bleb) or from the external environment (stab wound to the thorax) or a combination of both (shotgun blast to the thorax).

If air continues to accumulate in the pleural space with no opportunity for escape, a "tension" pneumothorax develops, which eventually compromises venous return to the heart and can be fatal.

Patients will gradually develop worsening shortness of breath, distended neck veins, tracheal deviation away from the side of the injury, hypoxia, hypotension, tachycardia and eventual death if left untreated.

Figure 2

Figure 2.

Chest x-ray demonstrating right sided pneumothorax

Hemothorax: presence of blood in the pleural space. Usually occurs as a result of penetrating injuries to the thorax. Clinical appearance can mimic pneumothorax, and if a large volume of blood accumulates in the chest, can result in more rapid onset of hypotension.

Pericardial tamponade: fluid or blood accumulates in the pericardial space, and results in muffled heart tones on auscultation. Neck veins will become distended with worsening tamponade, and hypotension with a narrowed pulse pressure will be seen.

Blunt Abdominal Trauma

Figure 3

Figure 3.

CT abdomen/pelvis with IV contrast demonstrating liver laceration

Solid or hollow viscus injuries that occur as a result of blunt trauma usually present with abdominal pain. This may be accompanied by hypotension and tachycardia.

Outward signs of injury include a "seatbelt sign," which is a bruise or contusion in the distribution of a seatbelt, distension, and dullness to percussion.

Figure 4

Figure 4.

Penetrating Abdominal Trauma

Evaluation of penetrating trauma to the abdomen includes the size and shape of the injury, and if possible, an assessment of the underlying fascia. If the anterior fascial layer is penetrated, these patients will often be evaluated with either observation and bowel rest or diagnostic laparoscopy.

Primary ATLS survey

Airway

Breathing

Circulation

Secondary ATLS survey

Head-to-toe examination

Definitive triage with further imaging or admission to a ward with the necessary level of care.

2. Emergency Management

As with all trauma patients, the initial focus should be directed at stabilizing the hemodynamics and performing a primary survey, as dictated by ATLS. Specifically, attention be directed to the ABCs: Airway, Breathing, and Circulation.

These issues should be resolved in a stepwise fashion, in the order listed. Once these issues are stable and immediate problems resolved, the physician can move on to a more comprehensive examination of the patient.

Surgical evaluation is oftentimes warranted, and ideally the surgeon will be present from the time of the initial resuscitation. However, initiation of ATLS protocols does not mandate the presence of a surgeon, and all physicians responsible for the care of injured children should be facile with the algorithms.

Management points not to be missed

Airway: is the patient maintaining a patent airway on their own? Can they speak? Do they appear to be oxygenating and ventilating appropriately? Are they in a cervical spine immobilizer?

Oxygen should be placed on the patient. If the patient is unable to maintain an airway or adequate oxygenation/ventilation, they should be intubated with in-line stabilization of the cervical spine.

Breathing: Are they moving air in and out spontaneously? Are the breath sounds equal on both sides of the chest?

Obtain a chest X-ray for review. If air movement is unequal and there is concern for a tension pneumothorax, perform a needle thoracostomy at the second intercostal space in the mid-clavicular line.

Secondary survey consists of a head-to-toe examination of the child after removing all clothing.

Hypothermia is a significant issue for all trauma patients, but particularly infants and toddlers. Special attention should be made to prevent hypothermia--warm the trauma bay, use heated airflow machines, warmed blankets, warmed intravenous fluids.

Drugs and dosages

Code drugs can often be administered intravenously, or if that is not a possibility, intratracheally. Specific drugs that should be available in the Emergency Department for rapid use include:

Succinylcholine

Etomidate

Rocuronium

Versed

Fentanyl

Epinephrine

Atropine

Phenylephrine

Dopamine

Adenosine

For dosing instructions, please see chapter on CPR.

3. Diagnosis

Diagnosing the specific type of thoracic injury is helped by knowledge of the inciting mechanism. All evaluations should begin with gathering information about the circumstances surrounding the injury from primary responders (nurses, EMTs, fire/police department).

A complete exam is warranted, but is usually performed in stages, beginning with a primary survey. Imaging modalities that can be performed in the trauma bay include ultrasound and chest X-ray.

Computerized tomography (CT) is frequently useful but carries with it the additional radiation exposure. The decision to proceed with a CT scan should take into consideration the additional exposure to ionizing radiation.

Initial efforts should be directed at stabilizing the patient. As the ABCs are evaluated, any issues identified should be dealt with before proceeding on to the next step in evaluation.

For instance, if a patient is unresponsive and unable to protect their airway, intubation should be the priority before moving on to assessment of breathing and circulation.

Once hemodynamic stability is achieved, a more thorough secondary survey can be performed in addition to further imaging studies.

Diagnostic tests

Initial imaging is as per ATLS protocol. This includes routine chest radiograph, pelvic film and lateral cervical films. The films should be read by someone experienced with pediatric films.

A normal thymus in an infant may be mistaken for a widened mediastinum. The open epiphysis on pelvic film may be mistaken for a fracture.

A Focused Abdominal Sonogram for Trauma (FAST) exam can be undertaken as in an adult. The FAST can identify pericardial-tamponade and free fluid in the abdomen.

If indicated a CT scan of the abdomen and pelvis is performed. Oral contrast is controversial; however, intravenous (IV) contrast is essential. Solid organ injuries can be easily missed without IV contrast. IV contrast also adds information about the abdominal vasculature as well as the GU system, where it is excreted.

A chest CT scan can be very helpful in the evaluation of a widened mediastinum. The chest CT should be ordered as a "CT angiogram" so that the arterial phase is well opacified for evaluation of the aorta. A chest CT scan is rarely indicated for pulmonary contusion, rib fracture, pneumothorax or other chest trauma in the absence of a widened mediastinum.

Hematocrit/hemoglobin - all patients.

AST/ALT - used to determine need for CT scan of the abdomen (either over 200), in conjunction with clinical exam.

PT/PTT - not usually necessary; although, can be helpful in patients with a head injury (with release of endogenous TPA), or those that have had massive hemorrhage.

Urine analysis - used to look for RBCs as an indication of abdominal/GU injury.

Pathophysiology

NA

Epidemiology

Trauma affects children and adults of all ages. The majority of trauma in the pediatric population is blunt, though urban centers see a larger proportion of penetrating injuries.